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Abstract We report on the temperature dependent low energy electron diffraction (LEED) studies of 12 nm epitaxial Sr₃Ir₂O₇(001) thin films. The Debye temperature has been extracted from the temperature-dependence of LEED intensity at elevated temperatures and different electron kinetic energies. For the most surface sensitive LEED, obtained at the lowest electron kinetic energies, the extracted surface Debye temperature is 270 ± 22 K, which is much lower than the 488 ± 40 K Debye temperature obtained using higher electron kinetic energies. Surprisingly, the LEED diffraction intensity, at the lowest electron kinetic energies, increases rather than decreases, with increasing sample temperatures up to about 440 K. This anomalous behavior has been attributed to the reduction of the lattice vibrational amplitudes along the surface normal. This damping of the normal mode vibrations with increasing temperature results from the enhanced electronic screening via thermally activated carriers. This scenario is corroborated by the transport measurement, showing that Sr₃Ir₂O₇is a narrow band Mott insulator with a band gap of about 32 meV. We have identified criteria for finding anomalous scattering behavior in other transition metal oxide systems. 

The example of spin crossover molecule [Fe(Htrz)2(trz)](BF4) (where Htrz = 1H-1,2,4-triazole) plus polyaniline composite thin films is used to illustrate the rapid improvement in transport properties signaling that competitive molecular devices for back end of the line (BEOL) silicon compatible nonvolatile memory arrays are increasing realistic. 

A Verilog-A based model for the magneto-electric field effect transistor (MEFET) device is implemented and a variety of logic functions based on this device are proposed. These models are used to capture energy consumption and delay per switching event and to benchmark the MEFET with respect to CMOS. Single-source MEFET devices can be used for conventional logic gates like NAND, NOR, inverter and buffer and more complex circuits like the full adder. The dual source MEFET is an enhanced version of the MEFET device which functions like a spin multiplexer (spin-MUXer). Circuits using MEFETs require fewer components than CMOS to generate the same logic operation. These devices display a high on-off ratio., unlike many magneto-electric devices., and they operate at very low voltages., resulting in lower switching energy. Benchmarking results show that these devices perform better in terms of energy and delay., for implementing more complex functions., than the basic logic gates.